async function wupexRequest(fn) {
  let retries = 0, delay = 500;
  while (retries < 5) {
    try {
      return await fn();
    } catch (err) {
      const code = err.status;
      if (![429].includes(code) && !(code >= 500 && code < 600)) throw err;

      retries++;
      const jitter = Math.random() * delay;
      await new Promise(r => setTimeout(r, delay + jitter));
      delay = Math.min(delay * 2, 10000);
    }
  }
  throw new Error("Max retries reached");
}